The purpose of Ron Paul's retirement from Congress, announced on Tuesday morning, is to allow the (now former) Texas congressman to focus on running for president.

There is a piece of irony, or perhaps fortuitousness, in the timing: rival presidential candidates like Michele Bachmann, along with a wave of Tea Party Congressional freshman, have risen to power by espousing a version of the small-government libertarianism that has long been Paul's trademark. Should he fail to secure the nomination -- a likely outcome, given that polls put him in Newt Gingrich territory -- he could face retirement just as the ideology he rose to prominence espousing is ascendant.

The Tea Party revolution was fueled by a sense that government had become overly large, intrusive and ineffective -- in other words, that it was the problem rather than the solution. Bachmann has built a career out of warning against the ills of government overreach, saying in a speech launching her candidacy that it was not true that government can create jobs, and make a better life for all of us, even make us healthier. The quote reads like a paraphrase of a gentler speech Paul once made on the floor of Congress.

I do not challenge the dedication and sincerity of those who disagree with the freedom philosophy and confidently promote government solutions for all our ills, he said. I am just absolutely convinced that the best formula for giving us peace and preserving the American way of life is freedom, limited government, and minding our own business overseas.

Paul has also generated some of the same voter excitement that propelled the Tea Party movement during the backlash to President Obama's healthcare proposal. His ability to raise large amounts of money in short bursts helped to drive more conservatives towards online fundraising.

There is perhaps no better example of Paul's influence than the election of his son, Rand Paul, to the Senate. The elder Paul has been dismissed as a fringe ideologue for his commitment to ending the Federal Reserve bank, and the younger Paul recently likened the obligation to provide universal healthcare to slavery. The younger Paul has also extended his father's staunch resistance to aggressive American foreign policy, fighting an extension to the Patriot Act and cowriting a New York Times op-ed urging the accelerated withdrawal of U.S. forces from Afghanistan.

Paul also retired ahead of the 1984 election and was re-elected in 1996, leaving open the possibility of a comeback if his presidential bid is unsuccessful. But if not, some residue of his beliefs is likely to inform future votes for years to come.