It’s looking like Rep. Doug Lamborn (R-Colorado Springs) will face his toughest primary challenger yet.

Owen Hill, a current state senator from the Colorado Springs area, raised about $228,000 from April to the end of June, according to online filings with the Federal Election Commission.

That’s the most money raised by a candidate in a single quarter since the seat was created in 1972. And it’s almost double the $115,000 Lamborn raised.

“I’m so humbled by the record-breaking support from employers and neighbors in our district and throughout Colorado,” Hill said. “The numbers speak for themselves.”

Hill appears to be challenging Lamborn from the right.

He promises to join the House Freedom Caucus and blasted the congressman for his "lack of commitment" on repealing Obamacare when he announced in April. Lamborn voted for the Republican healthcare bill when it passed in May, but he was undecided on the version that was pulled in April.

It’s a tough road for Hill or anyone challenging a sitting member of Congress.

Lamborn’s had a primary challenger every time he’s run except for once, and he’s defeated all of them. The 62-year-old incumbent crushed Calandra Vargas, his 2016 challenger, in the primary despite coming close to being kicked off the primary ballot at the 5th Congressional District Assembly.

And primary challengers don’t fare well in general.

Almost half of the incumbents running for the U.S. House of Representatives in 2016 faced a primary challenger, according to Ballotpedia. Five of those people lost their primaries – about 1.3 percent.

In fact, only 39 primary challengers have unseated a sitting member of the House since 1994.

Complicating this race further was the recent announcement by Darryl Glenn that he too will seek the nomination. The El Paso County Commissioner unsuccessfully ran against Sen. Michael Bennet (D-Colorado) in 2016.

9NEWS asked Lamborn for comment but has yet to hear back.

Lamborn’s still got more money in the bank than Hill. The five-term congressman has $378,553 cash on hand while Hill has $192,843, according to FEC filings.

But if Hill sustains his fundraising pace, it won’t be long before he overtakes Lamborn.

“This is just the tip of the iceberg,” Hill said. “Literally thousands of other folks have reached out who want to help me bring energy and competence to represent us in D.C.”