LOUISVILLE, Ky. — Senate Minority Leader Mitch McConnell picked up an endorsement Tuesday from a national tea party group, continuing his courtship of groups advocating limited government as the Republican tries to head off a primary challenge as he seeks a sixth term next year.

The endorsement from TheTeaParty.net comes as McConnell rakes in campaign cash and airs television ads while Democrats look for a challenger to the longest-serving senator in Kentucky history.

Todd Cefaratti, the tea party group's founder, said McConnell's support of spending cuts and defense of gun rights "makes him an indispensable ally of conservatives in the Senate."

McConnell has been vocal in calling for more budget cuts and recently voted against expanded background checks for gun sales.

McConnell campaign manager Jesse Benton said the endorsement was "a tremendous honor."

As the leader of Senate Republicans, McConnell has been a steadfast critic of President Barack Obama. He also has been cozying up to the tea party in hopes of heading off a GOP primary challenge next year.

Niger Innis, chief strategist for TheTeaParty.net, said Tuesday that it's "highly unlikely" that McConnell will face a challenger from within tea party ranks.

"We've had contacts with a variety of tea party groups in Kentucky, and they all seem to be circling the wagons around Sen. McConnell," he said in a phone interview.

McConnell was first elected to the Senate in 1984, and in past campaigns he has bragged about bringing federal money back to Kentucky. Innis said the times have changed, and so has McConnell.

"People are much more apprehensive about government largess and about the growth of government," he said. "And I think Sen. McConnell has gone with the times, and has been as sterling a conservative, tea party senator as he could possibly be."

Democrats are still looking for a challenger to McConnell. Secretary of State Alison Lundergan Grimes, seen as a political rising star within Democratic ranks, is considering a Senate bid but has given no timeframe for making a decision. Actress Ashley Judd had considered running but announced several weeks ago that she won't.

Democratic Gov. Steve Beshear has said he's been encouraged by supporters to run against McConnell. But Beshear, in his second and final term as governor, has said he won't seek election to any other office. Beshear lost to McConnell in a bruising 1996 Senate race.

Defeating McConnell would be the Democrats' biggest prize of the 2014 election. His seat is one of 14 that Republicans are defending, while Democrats try to hold onto 21.

McConnell, always a prolific fundraiser, reported more than $8.6 million on hand in his latest campaign finance report.