3700
Senator Elizabeth Dole , Republican of North Carolina and an advocate of the rule change , put subtle pressure on another uncommitted Republican , Senator Chuck Hagel of Nebraska , at a rally with him in his home state to campaign against Senator Ben Nelson , a Democrat up for re-election next year .
 Ben Nelson, Nebraska; Chuck Hagel, Nebraska
Please list all entity pairs containing a certain relationship in the given options.Output format is "word1, word2; word3, word4". 
Option: ethnicity, place lived, geographic distribution, company industry, country of administrative divisions, administrative division of country, location contains, person of company, profession, ethnicity of people, company shareholder among major shareholders, sports team of location, religion, neighborhood of, company major shareholders, place of death, nationality, children, company founders, company founded place, country of capital, company advisors, sports team location of teams, place of birth 
Text: {0} 
Answer:
 Ben Nelson, Nebraska; Chuck Hagel, Nebraska