Duke Alexander Petrovich of Oldenburg
... that because of his birth and marriage to a Russian princess, Duke Alexander Petrovich of Oldenburg was Russia's candidate to succeed Alexander, Prince of Bulgaria?
... that because of his birth and marriage to a <a href="./Princess_Eugenia_Maximilianovna_of_Leuchtenberg" id="mwAt4" rel="mw:WikiLink" title="Princess Eugenia Maximilianovna of Leuchtenberg">Russian princess</a>, <b id="mwAt8"><a class="mw-redirect" href="./Duke_Alexander_Petrovich_of_Oldenburg" id="mwAuA" rel="mw:WikiLink" title="Duke Alexander Petrovich of Oldenburg">Duke Alexander Petrovich of Oldenburg</a></b> was <a href="./Russian_Empire" id="mwAuE" rel="mw:WikiLink" title="Russian Empire">Russia</a>'s candidate to succeed <a class="mw-redirect" href="./Alexander,_Prince_of_Bulgaria" id="mwAuI" rel="mw:WikiLink" title="Alexander, Prince of Bulgaria">Alexander, Prince of Bulgaria</a>?