Democrats based their claim on an Aug. 21, 1990, letter from then-Secretary of State Blunt to an immigration commissioner requesting assistance for a Nicaraguan immigrant who was seeking political asylum in the U.S. In the letter, Blunt says the woman "has done some work for Roseann," who was his wife at the time.
The Democratic Party said the letter suggests the Blunts employed the woman before she got official approval to work in the U.S. Democrats said they obtained the letter through an open-records request to the secretary of state's office, which now is led by Blunt's Senate rival, Democrat Robin Carnahan.
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"Congressman Blunt hired an illegal worker and used his official office and Washington connections" to try to assist her immigration process, Corey Platt, a senior adviser at the Missouri Democratic Party said in a conference call with reporters.
Blunt spokesman Rich Chrismer called the assertion "just plain crazy."
"This person never worked for the Blunts," Chrismer said. "She simply helped out at a couple of church events.
"Constituents who are having problems with a government agency reach out to Roy Blunt all of the time and he passes this information on to the appropriate officials all of the time," Chrismer added. "This is desperate, dirty politics from Robin Carnahan's failing campaign."
Carnahan campaign spokesman Linden Zakula had no immediate comment about the assertions.
The immigrant is identified in Blunt's letter and other documents released by the Democratic Party as Dora Narvaez, of Jefferson City.
The Kansas City Star reported Tuesday that a woman identifying herself as Narvaez told the newspaper she had worked for the Blunts as a housekeeper for several months in 1990. But the Star said she declined further comment.
The Associated Press could not reach Narvaez on Tuesday. She did not immediately return a message left for her through the church she attends in Jefferson City. A resident at Narvaez's last publicly listed address said Narvaez had moved in April and had not left any contact information.
Roseann Blunt, who now is divorced from Roy Blunt, told the AP that she had shared her recollections of the situation with Blunt's campaign team and did not have anything to add to the statement released by Chrismer.
The letter from Blunt to immigration commissioner Gene McNary referenced an attached letter from Narvaez to Roseann Blunt, which the Democratic Party also released. In that July 23, 1990, letter, Narvaez said she had come to the U.S. in December 1988 and applied for political asylum in Los Angeles before traveling to Jefferson City to live with a sister. She said she had encountered trouble transferring her case to the Kansas City immigration office and needed helping getting a certain immigration document and an attorney.
A September 1990 letter from McNary to Blunt noted there were almost 90,000 pending applications for asylum, which were being processed in chronological order. McNary wrote that he had included a form for Narvaez to apply for employment authorization, if she had not already done so.