A new survey shows Sen. Lamar AlexanderAndrew (Lamar) Lamar AlexanderWeek ahead: Lawmakers near deal on children's health funding Ryan suggests room for bipartisanship on ObamaCare Time to end fiscal year foolishness MORE (R-Tenn.) crushing his main Republican primary opponent, state Rep. Joe Carr.

The survey, from Middle Tennessee State University, gives Alexander 47 percent support among Republican respondents, while Carr takes just 7 percent support.

Still, 40 percent are undecided on the race, meaning Carr could have time to make inroads into Alexander’s support before the August primary.

That aligns with an internal poll Alexander’s campaign released earlier this week, which gave him 62 percent support to Carr’s 17 percent.

Both surveys indicate the incumbent senator and former governor maintains high popularity with Republicans. The MTSU poll shows 59 percent of Republicans approving of his job performance, while just a quarter disapprove.

That’s an increase in the population that disapproves of Alexander’s job performance, up from 14 percent a year ago. Still, the survey shows him in a strong position heading into the final five months of the primary fight — and Carr has struggled to pick up much traction in the race, with the national conservative groups that can close the fundraising gap he faces so far sitting out.

MTSU surveyed 600 Tennessee adults from Jan. 23-26 via landline and cellphone. The poll has a margin of error of plus or minus 4 percentage points.