With just over a week remaining for Colorado voters to return their ballots, all eyes are on three of the state’s eight congressional districts, where voters in the state’s most competitive races could have a hand in determining which party controls the U.S. House of Representatives.

While the 2024 campaign season has been dominated by the race for the White House between Republican Donald Trump and Democrat Kamala Harris, Colorado no longer occupies the swing-state status it recently enjoyed, as its increasingly Democratic electorate means both sides are treating the state as safely in Harris’ column.

Colorado was the tipping-point state in both of Barack Obama’s wins, with its electoral votes putting the Democrat over the top in 2008 and 2012 after hard-fought campaigns that featured frequent visits from Obama and Republican nominees John McCain and Mitt Romney, respectively. Since then, however, Democrats Hillary Clinton and Joe Biden both easily defeated Trump to carry the state, with Biden winning Colorado by a wide 13.5 percentage point margin.

In addition to the three congressional districts, there’s plenty of action in the Colorado General Assembly.

Democrats are defending historic majorities in both chambers — the party holds a supermajority in the state House and is just one seat away from the same position in the state Senate — while Republicans are hoping to regain some of the seats the party has lost since the 2018 election, when Democrats won complete control of state government.

And, among a long list of ballot measures, voters are deciding whether to establish a right to abortion in the state constitution, whether to change the way most candidates make the ballot by creating a so-called jungle primary with ranked-choice voting in the general election and whether to ban the hunting of big cats. 

In the 8th CD: Yadira Caraveo versus Gabe Evans

That doesn’t mean that a handful of races in Colorado aren’t as up for grabs as this year’s national presidential contest appears to be, led by Democrat Yadira Caraveo’s white-knuckle bid for a second term in the closely divided 8th Congressional District, which has turned into one of the most competitive — and expensive — races in the country.

The only Colorado House district classified as a true toss-up, the 8th CD appears to be neck and neck between Caraveo and her Republican challenger, state Rep. Gabe Evans, with the candidates and their supporters flooding the airwaves and voters’ mailboxes with mostly negative attack ads. Stretching from Adams County suburbs north of Denver to Greeley in Weld County, the district is Colorado’s newest — created after the 2020 census — and was drawn to be a swing seat. It’s also the Colorado district with the largest share of Hispanic or Latino voters, making up about 40% of its population and a somewhat smaller share of the electorate.

The district has lived up to its billing.

After winning the district by just over 1,600 votes — less than 1 percentage point, in one of the closest House races in the country last cycle — Caraveo has been targeted by both national parties since soon after being sworn in, with the Democrats adding her to a program for vulnerable incumbents and the Republicans lobbing a continuous stream of attacks at her and bolstering Evans’ campaign with strategic advice and funding.

It’s considered a linchpin in the pitched battle for control of the House, where Republicans currently hold a slim seven-seat majority, meaning Democrats need only flip four seats to take the gavel next year. The vast majority of the House’s 435 seats are considered safe for one party or the other, leaving only a few dozen on the line, and for the second election running, Colorado’s 8th CD is among the most fiercely contested of those districts.

The seat ranks fourth nationally for spending by outside party and sympathetic groups — up a few slots from last cycle — according to a tally maintained by campaign finance data maven Rob Pyers. Through the morning of Oct. 24, party committees, PACs aligned with House leadership and outside groups had poured $21,745,267 into the 8th CD, with Democratic and liberal groups outspending Republicans and conservatives by just over $2.6 million.

The candidates and their allies have been hammering each other in TV, digital and direct mail.

Caraveo and the Democrats have spent millions branding Evans as “too extreme” for Colorado, citing his support for the Supreme Court decision that overturned Roe v. Wade and comments he made as a teenager opposed to same-sex marriage, before another Supreme Court decision made it legal nationwide.

At the same time, Evans and the Republicans blast Caraveo for “making things worse,” attempting to saddle her with the border crisis, crime and the flood of fentanyl into the district.

Different this cycle from two years ago, when a Libertarian candidate pulled about 4% of the vote — many times the slim margin between Caraveo and Republican Barb Kirkmeyer, a state senator — Evans could benefit from the endorsement he received just after Labor Day from the minor party’s nominee, who removed his name from the ballot.

Under the theory that Libertarians pull votes from Republicans, potentially costing GOP nominees a win in extremely close races, the two parties’ state chairs reached an agreement more than a year ago whereby Libertarians would stand down in competitive districts if they were convinced the Republicans upheld a list of core principles. After much negotiation, Evans signed on to a document pledging to adhere to roughly a dozen positions, paving the way for Libertarian Eric Joss to drop out in an effort to avoid “spoiling” the race by peeling off conservative-minded voters.

Underlining the race’s importance to both national parties, both House Speaker Mike Johnson, a Louisiana Republican, and House Minority Leader Hakeem Jeffries, a New York Democrat, have made multiple trips into the district to fundraise for the candidates and rally their supporters.

The face-off between Caraveo and Evans stands as Colorado’s marquee contest this year since there are only two races on the statewide ballot, for the presidency and the low-key race for the at-large seat on the University of Colorado Board of Regents. That only happens every dozen years, as statewide races for governor, attorney general, secretary of state and state treasurer fall in midterm years, and neither of Colorado’s two U.S. Senate seats is up in 2024.

Two other House races for open, GOP-held districts in Colorado could yield surprises on election night, though both are a ranked as safe Republican seats by most national election forecasters.

In the 3rd CD: Adam Frisch versus Jeff Hurd 

In the 3rd Congressional District, Democrat Adam Frisch, former member of the Aspen City Council, is making his second run in the sprawling district, which covers most of the Western Slope and parts of Southern Colorado, including Pueblo County and the San Luis Valley. One of the top House fundraisers in the country this cycle, Frisch is facing first-time Republican nominee Jeff Hurd, a Grand Junction attorney.

The district’s makeup and voting history suggest Hurd has the advantage, but Frisch, who pitches himself as a centrist unbeholden to his party, has been campaigning virtually nonstop for nearly three years and has so far outspent Hurd by an enormous margin, suggesting that the kind of upset he nearly accomplished two years ago might happen in November.

The country’s closest House race two years ago was in Colorado’s 3rd CD, where GOP incumbent Lauren Boebert came within just 546 votes of losing reelection in the Republican-leaning district. Frisch almost immediately launched a bid for a rematch and set about crushing state congressional fundraising records — billing himself as the Democrat who nearly unseated one of the most prominent and controversial House Republicans — hauling in many times campaign cash Boebert raised in every quarter last year.

Facing an uncertain future in the district on the heels of a scandal that generated international headlines — when Boebert and her date were ejected from a Denver production of “Beetlejuice: The Musical” for disruptive behavior — the Republican announced at the end of December that she was moving across the state to friendlier precincts in the heavily Republican, open 4th Congressional District to effectively seek a third term there.

In the 4rd CD: Lauren Boebert versus Trisha Calvarese 

Colorado’s deepest red seat, the 4th CD is anchored by suburban Douglas County and spreads across the Eastern Plains, including Loveland and parts of the northern Front Range. It’s only elected a Democrat once, for a single term, in the last 50 years, though that was two rounds of redistricting ago, when the seat’s electorate was more balanced and took place in 2008, the same year as Obama swept the state.

The seat became open late last year after five-term Republican Ken Buck announced he wouldn’t run for reelection. In a twist, Buck abruptly resigned in March, triggering a special election to fill the seat for the remainder of his term. Rather than run in the vacancy race, however, Boebert backed another Republican, Greg Lopez, who vowed not to seek a full term, since she would have had to resign the seat she currently holds in the 3rd CD.

Lopez won the special election by a comfortable margin over Democrat Trisha Calvarese, prevailing by 24 percentage points, which was about the same margin Buck enjoyed over his Democratic challenger in the two previous general elections.

Concurrent with that election in late June, Calvarese won a three-way primary at the same time that Boebert defeated four other Republicans in the GOP primary, setting up the state’s third competitive House race for the fall.

On paper, the 4th CD should be out of reach for a Democratic nominee, but Calvarese, a first-time candidate who moved back into the district about a year ago after growing up there, has made a race of it, out-raising the Republican since the primary after assuming the mantle Frisch cultivated as Boebert’s opponent.

Buffeted by a flood of small-dollar contributions from a national donor pool, Calvarese has been outspending Boebert by roughly 10-1 on broadcast, streaming and digital TV screens in a brutal air war premised on internal polling that found Boebert with unusual high negative ratings among the constituents she hopes to represent.

One of the consequences of Colorado dropping of the ranks of battleground states has been a dearth of neutral polling in down-ballot races. The single nonpartisan opinion survey conducted in the 8th CD shows a dead heat, with Caraveo and Evans each polling at 44% support, with 12% undecided, but there haven’t been any polls released by outside groups in the 3rd or 4th CDs.

In the most recent quarter, which ended on Sept. 30, Frisch swamped Hurd, spending nearly 10 times as much as the Republican, though conservative outside groups, chiefly the Koch Network’s Americans for Prosperity Action, which has spent close to $1 million on canvassing and advertising in an attempt to keep it close.

The district ranks near the bottom of Pyers’ list of outside spending in House races, coming in at No. 42 out of 49 contests that have seen that kind of spending, with just under $1.5 million reported through Oct. 24. Most of that has been by party committees and conservative outside groups — including AFP — giving Hurd’s side an advantage of about $300,000, though progressive outside groups have pumped nearly $600,000 into the race.

Without Boebert in the mix, however, neither party has yet allocated substantial resources to the seat. It’s the same story in her new, redder district, where both Calvarese and Boebert are pretty much on their own.

The rest of Colorado’s congressional districts

The state’s five remaining House districts appear to be firmly in their respective party’s corner.

The only seat among the five likely to send a new lawmaker to Washington is the reliably Republican 5th Congressional District, which has been represented since 2007 by Doug Lamborn, who announced his retirement at the beginning of the year. In the El Paso County-based district, former talk radio host and AFP executive Jeff Crank is on a glide path to election over Democratic nominee River Gassen.

Voters in the other four districts will almost certainly return their Democratic incumbents to the Capitol.

In the Denver-based 1st Congressional District, Democrat Diana DeGette is seeking a 15th term against GOP challenger Valdamar Archuleta.

Assistant House Minority Leader Joe Neguse is seeking a fourth term in the 2nd Congressional District, which covers Boulder and Larimer counties and includes mountain counties surrounding the Interstate 70 corridor to Vail. Republican Marshall Dawson is making his second run for the seat.

Also seeking a fourth term, Democrat Jason Crow is facing a spirited challenge from Republican John Fabbriatore in the Aurora-based 6th Congressional District.

Democratic lawmaker Brittany Pettersen is running for a second term in the Jefferson County-based 7th Congressional District, which reaches south along the Continental Divide past Cañon City, against GOP challenger Sergei Matveyuk.