在台灣，許多研究者認為因為多數立法委員享有雄厚的基層實力，所以在不同選舉中，可獲得機乎同一批選民的支持，此篇論文即著眼於，檢證這個假設。此篇論文所採用的研究方法是分析候選人得票率最高的地區，在此地區尋找不穩定的蹟象。 大體而言，我們發現多數候選人的支持基礎並不穩定。於不同次選舉之間，候選人的地盤可能發生不少變動。換言之，有不少候選人是依賴相異的票源基礎而連任。影響候選人地盤穩定最重要的變數是候選人故鄉人口的多寡。來自較大鄉鎮市的候選人，地盤較為穩定。

It is generally assumed that strong grassroots support ensures that Taiwanese legislators get support from the same voters over repeated elec-tions. This paper attempts to test this hypothesis. We look at each candi-date's strongest areas in each election. By comparing these areas over several elections, we can search for evidence of instability in his or her vote support. In general, we find that there is far less stability in support patterns than might be expected. It is rare that all of a candidate's strongest areas in one election are included in his or her strongest areas in subsequent elections. In other words, many legislators have been elected and re-elected with significantly different patterns of support. For the over-whelming majority of candidates, the crucial variable in determining sta-bility is the size of their hometowns. Candidates from large townships generally have more stable support, while those from smaller townships have less stable support.