WASHINGTON — Southwest Securities Inc. has agreed to pay $470,147 to settle charges with the Securities and Exchange Commission for violating an anti-pay-to-play rule by co-underwriting Massachusetts bond deals within two years after its former senior vice president made political contributions to state Treasurer Timothy Cahill.

The SEC also brought an administrative proceeding against former Southwest Securities official, John Kendrick, who was fired from his job last year. Kendrick, 65, worked in the firm’s Medfield, Mass., branch office between Dec. 1, 2000, and July 2009.

In addition to personally contributing $1,625 to Cahill between 2003 and 2008, Kendrick co-hosted a June 2005 fundraiser for the treasurer in which he made 82 solicitation requests for campaign contributions that netted $9,000, the SEC said.

The commission said the conduct of Southwest and Kendrick violated the ­Municipal Securities Rulemaking Board’s Rule G-37 on political contributions. The rule prohibits firms from engaging in ­negotiated municipal securities business with an issuer for two years if they, their muni finance professionals, or political action committees make significant ­contributions to the issuer’s officials or candidates.

The SEC noted that Cahill is responsible for, or can appoint people who are responsible for, hiring dealers to underwrite the state’s muni bond sales, as well as for related state governmental units. As a result, he is an issuer official under the rule.

While the SEC sometimes refrains from discussing the origins of its cases, a commission official suggested this particular case stems from a careful review of the political contributions that municipal finance professionals, or MFPs, have made to elected officials.

“We did not get this case through any outside tip or complaint,” said David Bergers, director of the SEC’s Boston regional office. “We uncovered this violation by taking a proactive approach to identifying potential pay-to-play violations.”

“We will continue to hold firms and individuals accountable when they violate the municipal securities’ pay-to-play rules,” he added.

Kendrick’s contributions were made in seven different checks during two election cycles. Before the 2006 primary, he contributed $250 on three occasions, for a total of $750, which was well above the MSRB’s $250 de minimis level of contributions that MFPs can make to candidates for whom they are eligible to vote.

During the second cycle prior to the 2010 primary, Kendrick contributed a total of $875 through four separate checks, with the latter three in excess of the $250 de minimis exception, the SEC said. The last contribution was made just under two years ago, on April 28, 2008.

A Southwest Securities spokesman declined to comment and Paul Hogan, of Hogan & Mercado PC in Milton, Mass., who is representing Kendrick, did not respond to phone calls.

A Financial Industry Regulatory Authority report on Kendrick shows that he was terminated last summer for his failure to report political contributions, follow firm policies and procedures concerning the filing of an annual employee questionnaire, and disclose “outside business activities.”

Kendrick has 20 days to respond to the SEC’s allegations. If he does not settle the charges, a public hearing will be held before an SEC administrative law judge.

The $470,147 that Southwest Securities is to pay the federal government includes a $50,000 civil penalty, disgorgement of $348,154 of ill-gotten fees obtained from co-managing 19 negotiated underwritings totaling $14 billion, and $71,993 in prejudgment interest.

Cahill was not accused of any wrongdoing in the SEC actions. But this is not the first time that he has been allegedly tied to accepting campaign contributions in exchange for state business, as he has battled accusations that he rigged lottery contracts in exchange for campaign donations. The pay-to-play allegations also extend to the state’s $40 billion pension fund, according to the Wall Street Journal.

Cahill left the Democratic Party last year and is an independent 2010 gubernatorial candidate. In a statement Wednesday, his campaign said: “The campaign had no knowledge that John Kendrick was in violation of SEC rules at the time of the contributions. The campaign will return any donations that are in violation of SEC regulations.”

Wednesday’s settlement and administration proceeding come less than a week after the SEC issued an unusual report showing that JPMorgan did not comply with s G-37 after its former vice chairman made contributions to, and solicited them for, Phil Angelides, who was California treasurer at the time.

The SEC did not charge JPMorgan with any violation of the rule or recommend any enforcement action. It said the report was meant to clarify to market participants that bank holding company executives affiliated with municipal dealers are not exempt from G-37’s pay-to-play restrictions if they have oversight of muni dealer operations.

Angelides, who now chairs the Financial Crisis Inquiry Commission, was not accused of any wrongdoing.