The spouse of a U.S. citizen who lives in Pennsylvania may be qualified for naturalization under the Immigration and Nationality Act. There are, however, several eligibility requirements that have to be met for this to occur. To be qualified to become a U.S. citizen, the spouse of an American citizen has to be at least 18 years old and lived within Pennsylvania for a minimum of three years before applying for naturalization. The residence in which the spouse has lived during the previous three years as a permanent resident must be a continuous residence, and the spouse has to live continuously in the country from the time of application until the date of naturalization.
A spouse also has to be physically in the country for a minimum of 18 months out of the three years that the individual held a continuous residence. The spouse needs to be capable of speaking, reading and writing English and understand and know about U.S. government and history. Additionally, the individual must be of respectable moral character, be acceptably disposed to the happiness and good order of the country during relevant periods and be attached to the Constitution's principles.
There are exceptions to these requirements for spouses of U.S. citizens who work abroad. While the spouses have to be permanent residents, they do not have to be physically in the country or living in a continuous residence for a specific time frame, nor be a permanent resident for a certain period. The spouses also do not need to be married for a specific amount of time as long as their marriages are valid when applying.
While some spouses may have a general understanding of these requirements and how to apply for naturalization, the process could be confusing. Interested parties may wish to speak to an attorney about the eligibility requirements as well as the application procedure itself.
Source: USCIS, "U.S. Citizenship", November 17, 2014