“Follow the money” is often a reliable guide to explain how U.S. House and Senate members are acting the way they do.

The fiduciary rule could very well be a case in point.

Anti-fiduciary-rule money is flowing into the campaigns of Congressional opponents by the many hundreds of thousands of dollars.

Insurer Primerica, which has hired top Wall Street anti-regulatory lawyer Eugene Scalia to fight the rule, is the third top individual contributor for the re-election campaign of Georgia Republican Sen. Johnny Isakson, according to the Center for Responsive Politics. According to the center’s website, the company contributed $79,550 to his campaign for the period from 2011 to 2016. Isakson is the lead Senate sponsor of a resolution to overturn the rule.

The insurance sector, as a whole, ranks No. 2 in specific industry sources of cash for Isakson at $364,700.

Since the repeal initiative would almost certainly not survive a presidential veto if it passes—and since only one federal regulation has been voided by Congress in over 20 years—the effort would seem a pointless waste of time.

But with the importance Congress places on pleasing campaign funders (in the hopes of getting more), it pays to make as big a show as possible. So opposing the “best interest standard” probably wasn’t seen as a waste of time by John Kline, chair of the House Education and the Workforce Committee, when he took the rare step of holding a committee vote on an anti-fiduciary resolution.

With a potential loss of Republican control of the House if Donald Trump is nominated for president, GOP fund-raising for the seats has acquired an added urgency since there are only six months to go before the November general election.

In addition to the insurance sector’s contribution of well over $300,000 for Isakson, the industry has given $55,000 to House and the Workforce Committee member Brett Guthrie of Kentucky, $44,000 to Alabama’s Bradley Byrne, $31,000 to Michigan’s Mike Bishop, $21,000 to Wisconsin’s Glenn Grothman and $134,300 to Indiana’s Luke Messer.

In addition, Messer has taken in $11,500 from the mutual fund industry trade group Investment Company Institute’s PAC and $83,400 from the securities and investment industry.

Insurance and securities industry money accounts for roughly one out of every five dollars the Republican incumbent has received.

The securities and investment industry has also placed $189,600 in the campaign war chest of Nevada member Joe Heck, who is running in one of the costliest Senate contests this year. He and his likely Democratic opponent, Catherine Cortez Masto, are the runaway favorites to get their parties’ nods in the June primary and have each raised over $5.5 million from all sources.

Hedge fund Elliott Management is Heck’s largest individual contributor with $33,400.

Elliott Management also has given $48,400 to New York’s Elise Stefanik, who sits on the House Education and the Workforce Committee.

Stefanik has also received $199,188 from the securities and investment industry and $68,080 from the insurance industry.

The securities and investment industry has also contributed $30,108 to Virginia’s Dave Brat, $89,750 to Florida’s Carlos Curbelo and $31,460 to Georgia’s Rick Allen.

Money from the insurance industry or from the securities and investment industries is not among either the top five individual or industry contributors for nine of the 22 Republican committee members running for re-election.

Kline personally has taken in no anti-fiduciary dollars because the six-term Minnesota representative is not running for re-election. Nor is Arizona member Matt Salmon.