Sen. Lamar AlexanderAndrew (Lamar) Lamar AlexanderIBM-led coalition pushes senators for action on better tech skills training Dems seek to leverage ObamaCare fight for midterms GOP senator: DOJ's ObamaCare argument 'as far-fetched as any I've ever heard' MORE (R-Tenn.), boosted by a significant second-quarter fundraising sum, is going on air with an ad that features Sen. Rand PaulRandal (Rand) Howard PaulSenate passes 6B defense bill This week: House GOP caught in immigration limbo Amendments fuel resentments within Senate GOP MORE (R-Ky.) touting his work defending fishing access.

Alexander brought in $2 million in the second quarter, a campaign aide confirmed, and is going on air with a $180,000 buy.

The aide said Alexander had already planned to go up with reelection ads early in the 2014 cycle and decided to focus the ad on the Freedom to Fish Act because it's an issue Tennesseans care about.

But it's also an issue that allows Alexander to highlight his work curbing government regulations, something that appeals to Tea Party voters.

Conservatives have indicated they'd like to challenge Alexander in a primary next year, with the Senate Conservatives Fund telling supporters last week that his vote for the immigration reform measure that passed the Senate makes him open to a primary challenger that they'd be willing to back.

"We don't want a government that's strong enough to make our lives risk-free. We can do that for ourselves," Alexander says in the video.

Paul's inclusion in the video is designeded to boost Alexander's credibility among the grassroots Tea Party activists. 

"Nobody wants to say no to Lamar Alexander," Paul says in the ad.

The Freedom to Fish Act also features prominently in a Web video released by the campaign of Senate Minority Leader Mitch McConnellAddison (Mitch) Mitchell McConnellSenate passes 6B defense bill Poll: Kim Jong Un has higher approval among Republicans than Pelosi The Hill's Morning Report — Sponsored by PhRMA — Outcry raises pressure on GOP for immigration fix MORE (R-Ky.), who is also considered to be vulnerable to a primary challenge.

Watch the ad: