Democratic Rep. Henry Cuellar of Texas invited his supporters to attend a fundraising breakfast for neighboring Texas Rep. John Carter on Tuesday.

The hook: Carter is a Republican in what experts expect to be one of the closest congressional races in the state.

Cuellar, the co-chair of the Blue Dog Coalition, a cohort of centrist Democrats, has a long history of bucking his party on policy issues including gun control — he has accepted money from the National Rifle Association for years now — and the Obama administration’s border security and deportation policies.

But it is highly unusual for a Democrat to link in an email directly to a fundraising page for a Republican colleague in an election year where Democrats are licking their chops to flip 24 seats and win back control of the House.

Tickets for the breakfast cost as much as $2,700.

Cuellar’s email to his supporters, first reported by Politico, and attendance at the breakfast at San Antonio’s Mi Tierra Cafe are not tantamount to an endorsement of Carter or a rejection of Carter’s Democratic challenger in Texas’ 31st District, former Air Force pilot M.J. Hegar, an aide told the Dallas Morning News.

“The congressman hasn’t taken any kind of position on that match-up,” Colin Strother, a Cuellar aide, told the Morning News. “He and Judge Carter have a long history of working together. Judge Carter has co-sponsored 16 of our bills and we have co-sponsored 13 of his bills. The congressman is a member in good standing [of the DCCC] and has not only paid his entire dues for this Congress but he is also advanced his dues for the next Congress.”

Carter will use all the help he can get in his contentious bid for re-election.

Hegar had a $500,000 leg up in total fundraising by the end of the Federal Election Commission’s second filing quarter and $330,000 more in cash on hand than the incumbent, according to the FEC’s online database.

President Donald Trump carried the district by 13 points in 2016, usually a safe mark for incumbent Republicans, but deficits that Democrats in other districts have erased in special elections since the 2016 midterms.

Inside Elections with Nathan L. Gonzales rates the race Likely Republican.

Carter spokesman Bruce Harvie said his boss, a former trial judge, was happy to have Cuellar at his fundraiser.

“The congressmen have a long friendship and share a strong belief in the power of bipartisanship. Judge Carter believes bipartisan relationships are especially important given the current climate in Congress. He’s honored to call Rep. Cuellar a friend and colleague and enjoys working with him for the betterment of all Texans,” he said by email.

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